Slip ring assemblies are well known and have wide-spread use where a plurality of electrical circuits must be maintained between a rotating member and a fixed member. It is well known by those skilled in the art, that a small, slowly rotating slip ring operating in a clean environment is very reliable and causes few problems. Conversely, high slip ring surface speed, unstable brush members and contaminents are some of the conditions that contribute to electrical noise or poor signal quality.
Most manufacturers of slip ring assemblies used for instrumentation, use a plurality of brushes mated to each slip ring in an effort to alleviate these problems. Also, if the end of the rotating member is accessible, a miniature slip ring assembly such as U.S. Pat. No. 3,185,951, can be attached to the end of the rotating member, thereby greatly reducing the slip ring surface speed.
U.S. Pat. No. 3,226,666 and U.S. Pat. No. 3,509,399 show slots incorporated into these designs in an effort to remove contaminents.
Brush lifters are well known and are frequently used to hold the brush members away from the slip rings during time periods when an electrical connection to the rotating member is not required. An example is shown in U.S. Pat. No. 1,661,014.
Another consideration is the case of cleaning, inspection and maintenance; especially in the case of a slip ring assembly which must be mounted on the rotating member itself. For example, on a drive shaft connecting a prime mover with some type of apparatus. In this example the slip rings must necessarily be larger in diameter than the rotating member. It is this type of application with which the present invention is primarily concerned.